Liquid fuel burner



J y 30, H. c. SHAGALOFF 2,209,443

' LIQUID FUEL BURNER Filed July 14, ,1937

ATTORNEY.

Patented July 30, 1940 UNITED STATES LIQUID FUEL BURNER Harry G. Shagalofl, Evansville, Ind., assignor to Servel, Inc., New York, N.

Delaware Y., a corporation of Application July 14, 1937, Serial No. 153,475

8 Claims.

My invention relates to liquid fuel burners, and it is an object of the invention to provide an improvement to obtain an even and uniform flow of liquid fuel to aburner.

The above and other objects and advantages of'my invention will be better understood from the following description and accompanying drawing forming a part of this" specification, and of which:

Fig. 1 illustrates a liquid fuel burner embodying the invention with the burner being shown partly in elevation and partly in section;

Fig. 2 is an enlarged fragmentary sectional view taken on line 22 of Fig. 1; and

Fig. 3 is a sectional view taken on line 33 of Fig. 2.

Referring to Fig. 1, a liquid fuel, such as kerosene, for example, is delivered from a suitable source of supply to an inlet In of a casing II. From the outlet l2 of the casing liquid flows through a conduit l3 and tube l4 to a burner well |5inwhichthefue1is vaporized. Above the burner well l5 are disposed spaced perforated chimneys I6 and I1, only the upper parts of which are shown, and about the chimneys is provided an enclosed shell I8.

Between the outlet l2 of casing II and conduit 13 is connected a safety valve IS. The valve I3 is provided with a weighted valve member 20 to v which is attached a lever 2|. The lever 2| is pivoted on a bracket 22 which is rigidly secured to the casing of valve l9. A link 23 of fusible metal is fitted over the outer ends of lever 2| and bracket 22 to keep the weighted valve member 20 in its upper position and thereby permit the flow of liquid to the burner. When the link 23 melts due to an abnormal rise in temperature of the burner, the weighted valvemember 20 moves downward to its closed position and shuts off the flow of liquid to the burner.

A partition 24 is provided in casing H to form a float chamber 25 and an overflow chamber 26 which communicates with the outlet l2. A vertical sleeve 21 located in float chamber 25 is secured at its lower end in anopening which communicates with the inlet I0. A valve seat 28 is formed at the lower end of sleeve 21, and above the valve seat are located openings 29 in the wall ofthe sleeve. To the upper end of sleeve 21 is secured a bracket 30 having pivotally mounted thereon an arm 3| of afloat 32. The rounded bifurcated ends 33 of arm 3| fit into a reduced portion of needle valve 34 which is vertically movable in sleeve 21. The float 32 and needle valve 34 control the flow of liquid through inlet 10 into float chamber 25 in a well-known manner to maintain a'substantially constant liquid level in the float chamber.

The lower horizontal part of partition 24 is provided with an opening to receive the lower threaded end of a hollow sleeve 35 which extends upward in chamber 26. Intermediate the ends of sleeve 35 is provided an opening or cut-out portion 36 which extends half-way about the sleeve, as shown most clearly in Fig. 2. The bore of sleeve 35 is reduced below the opening 36 to form a passage 31. Liquid flows from chamber 25 into the lower end of passage 31 through a slightly narrower passage 38 which'is formed in the lower end of sleeve 35.

The passage 31 is adapted to receive a valve 39 having a stem 40 extending upward therefrom. The stem 40 is provided with an enlarged portion 4| which is in threaded engagement with the upper part of sleeve 35, A control knob 42 is fixed to the upper end of stem 40 which extends through an opening in a removable cover plate 43 of casing The valve 39 is cylindrical in shape and is provided with a V-shaped slot which extends vertically along the side thereof. The slot 45 is tapered and starts from the surface of the valve 39 at the upper part and increases in size toward the lower part, as shown most clearly in Fig. 1. When'valve 39 is raised a slight distance from the lower end of passage 31, the V-shaped slot 45' provides a restricted passage for flow of liquid.

Due to the fact that there is some clearance between the valve 39 and the wall of passage 31, the position of slot 45' in passage 31 may vary under diflerent conditions. In order to keep the lower end of slot 45-in constant relation with respect to passage 31 and thus insure a uniform flow of liquid, a bowed spring 44 is secured to stem 40 and frictionally engages the inner wallof sleeve 35. The spring 44 also prevents accidentalmovement of valve 39 after it is adjusted to a desired position.

When valve 39 is in its closed position'and float chamber 25 is filled with liquid, the operation of the burner is started by raising valve 39 a slight distance to permit flow of liquid from chamber 25 through the restricted V-shaped passage 45. The liquid flows overthe lower edge of opening 36 into chamber 26, and thence through conduit l3 into burner tube l4. With flow of liquid out of chamber 25, the float 32 is lowered and needle valve 34 is raised from the valve seat 28, and liquid flows into chamber 25 from inlet l0 until the liquid is again at such a level that float 32 closes needle valve 34. When this occurs the liquid in burner tube l4, chamber 26, and chamber 25 are substantially at the same level. Upon igniting the liquid in the burner, fuel is consumed from the upper end of burner tube l4, and the liquid level'falls in tube l4 and chamber 25.

The level of liquid in chamber 26 is dependent upon the rate at which fuel is consumed from the upper end of burner tube I4, and, due to the pressure head resulting from the difference in liquid level in chamber 25 and in sleeve 35, the flow of liquid continues from chamber 25 into chamber 26. This flow of liquid is dependent upon the extent that valve 39 is opened in sleeve 35.

The flow of liquid at the overflow point of sleeve 35, that is, at the lower edge of opening 36, is not uniform because of a non-predictable meniscus being formed about the valve 39 and inner wall of sleeve 35. When accurate control of the burner flame is of considerable importance and a steady and uniform flow of liquid is desired, any sudden change in the rate of flow of liquid at the overflow point is objectionable.

In accordance with my invention, in order to obtain a substantially even and uniform flow of liquid to the burner, I provide a surface which extends downward at an angle from the overflow point to provide a capillary drain for flow of liquid. I accomplish this by providing two grooves or slides 45 at the lower edge of opening 36. At the lower edge of opening 36 is formed a lip 46, and the slides or grooves 45 extend downward at an angle from a point inside the lip 46 to the outer wall of sleeve 35.

In using a burner of the character described in which the sleeve 35 is provided with the grooves 45, I have discovered that the flow of liquid'at l the overflow point is steadied considerably and that a more even flow of liquid is obtained than when using a sleeve in which the grooves are omitted. Although-I do not wish to be limited thereto, it is my belief that the capillary flow of liquid takes place in the corners of the grooves to provide descending wet surfaces. The flow of liquid is steadied considerably due to the fact that the capillary flow takes place at surfaces which are at an acute angle to the vertical. When the liquid level increases at the surfaces of the grooves 45, for example, the effect of capillary flow is gradually diminished. This is a distinct advantage in obtaining a uniform flow of liquid in that the effect of capillary flow cannot be eliminated with an increase in liquid level at the grooves 45 to suddenly increase the flow of liquid at the overflow point.

While I have shown two grooves or slides at the overflow point in sleeve 35 to provide descending wet surfaces, it will be apparent that a single wider groove may be formed at the lower edge of opening 36 to steady the flow of liquid. It will also occur to those skilled in the art that a descending wet surface for liquid at the oversaid chamber, a-valve for controlling flow ,of Z5 flow point may be provided in other ways without departing from the spirit and scope of my invention. I therefore aim in the following claims to cover all changes and modifications which fall within the-true spirit and scope of the invention.

- What is claimed is:

- l. In a liquid fuel burner having a constant level chamber a passage communicating with liquid in said passage, said passage having an overflow point below the normal liquid level in said chamber whereby a pressure head is provided to cause flow of liquid at said overflow point, and a surface extending downward at said overflow point in such a manner that capillary flow of liquid is effected to wet such surface and thereby steady the flow of liquid.

2. In a liquid fuel burner having a constant level chamber, structure forming a passage communicating with the lower part of said chamber and extending vertically upward, said passage having an overflow point below the normal liquid level in said chamber, and said structure being so constructed and formed that a wetted surface is produced at said overflow point by capillary flow of liquid on such surface.

3. In a liquid fuel burner having a burner well and a constant level chamber, a conduit for conducting liquid fuel from said chamber to said burner and including a vertically extending member, said member having a discharge opening below the normal liquid level in said chamber, and said member at the opening having a sloping surface over which capillary flow of liquid is effected.

4. In a liquid fuel burner having a burner well and a constant level chamber, a conduit for conducting liquid fuel from said chamber to said burner and including a vertically extending hollow sleeve, said sleeve having an opening in the wall thereof below the normal liquid level in said chamber, and said sleeve at the opening having a surface sloping downward and outward and over which capillary flow of liquid is effected.

5. In a liquid fuel burner having a burner well and a constant level chamber, a conduit for conducting liquid fuel from said chamber to said burner and including a vertically extending hollow sleeve, said sleeve having an opening in the wall thereof below the normal liquid level in said chamber, the lower edge of said opening having a groove providing a surface at an angle to the vertical and over which capillary flow of liquid is effected.

6. In a liquid fuel burner having a burner well and a constant level chamber, a conduit for conducting liquid fuel from said chamber to said burner and including a vertically extending member, said member having a discharge opening below the normal liquid level in said chamber, and said member at said discharge opening having a groove providing a surface at an angle to the vertical and over which capillary flow of liquid is effected.

'7. In a liquid fuel burner, the improvement which consists in producing a pressure head between two communicating bodies of liquid fuel to cause flow of liquid from an overflow point in one of said bodies, flowing all of the liquid from said overflow point to the burner, and steadying the flow of liquid at said overflow point by causing capillary flow of liquid over a descending surface whereby the latter is kept in a wetted state.

8. In a liquid fuel burner, a burner well, a constant level fuel chamber, an overflow conduit from said chamber to said burner well and having a restriction, and also an overflow region below the normal liquid level in said chamber, and a descending surface, at said overflow region at an angle to the vertical and overwhich capillary flow of liquid is effected to keep such surface in a wetted state.

, i HARRY, C. SHAGALOFE 

